636
FXUS66 KOTX 102250
AFDOTX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPOKANE WA
350 PM PDT FRI OCT 10 2025
KEY MESSAGES
- EARLY WINTER STORM FOR THE NORTHERN MOUNTAINS FROM THE
NORTHERN WASHINGTON CASCADES TO NORTH IDAHO SUNDAY INTO
MONDAY MORNING.
- GUSTY NORTH TO NORTHEAST WINDS ON MONDAY.
- BELOW NORMAL TEMPERATURES SUNDAY INTO EARLY NEXT WEEK WITH
HIGHS IN THE 50S. LOW TEMPERATURES DROPPING INTO THE 20S AND
30S BY TUESDAY.
SYNOPSIS
CLOUD COVER AND PRECIPITATION CHANCES EXPAND ACROSS THE REGION
TONIGHT. THE WEEKEND BRINGS BREEZY CONDITIONS, MUCH COOLER
TEMPERATURES, AND CONTINUED PRECIPITATION WITH SNOW IN THE
MOUNTAINS. HEAVY SNOW WITH WINTER CONDITIONS IN THE NORTHERN MOUNTAINS
ABOVE 3000 FEET. DRY WITH TEMPERATURES WARMING TO NEAR NORMAL
NEXT WEEK.
DISCUSSION
...EARLY SEASON WINTER STORM TO BRING HEAVY SNOW TO THE
MOUNTAINS OF THE NORTHERN WASHINGTON CASCADES TO NORTH IDAHO...
TONIGHT THROUGH SATURDAY NIGHT: A DEEP LOW PRESSURE SYSTEM IS
SPINNING OFF OF THE OREGON COAST THIS AFTERNOON. GOOD SUPPORT
ALOFT AHEAD OF THE LOW WITH POSITIVE VORTICITY ADVECTION AND
DIFFLUENCE ALOFT WILL BRING FAVORABLE DYNAMICS. THIS ALONG WITH
INCREASING MOISTURE WILL RESULT IN WIDELY SCATTERED SHOWERS
PRIMARILY NEAR THE CASCADE CREST AND THEN ALSO OVER EXTREME
EASTERN WASHINGTON AND IN THE IDAHO PANHANDLE. MODEST
INSTABILITY AT MID LEVELS MAY RESULT IN A FEW EMBEDDED
THUNDERSTORMS. OTHERWISE, WE ARE LOOKING AT MAINLY PASSING LIGHT
TO MODERATE RAIN SHOWERS WITH THIS LOW AS IT EJECTS ACROSS
TONIGHT. WINDS WILL INCREASE OVERNIGHT INTO SATURDAY WITH BREEZY
CONDITIONS ACROSS THE COLUMBIA BASIN AND INTO THE SOUTHERN TO
CENTRAL IDAHO PANHANDLE. SOUTHWEST WINDS WILL BE PARTICULARLY
GUSTY ON SATURDAY ACROSS THE PALOUSE WITH GUSTS UP TO BETWEEN
20-30 MPH EXPECTED. A SHORTWAVE DISTURBANCE PUSHING ACROSS IN
THE NORTHWEST FLOW FOR SATURDAY NIGHT WILL DELIVER ANOTHER ROUND
OF PRIMARILY RAIN INTO THE IDAHO PANHANDLE. THIS NEXT SHOT IS
MORE LIKELY TO DELIVER WETTING RAINS ACROSS THE IDAHO PANHANDLE
WITH BETWEEN TENTH AND A QUARTER OF AN INCH OF RAINFALL
EXPECTED.
SUNDAY THROUGH MONDAY: BIGGER IMPACTS ARE ANTICIPATED WITH A
SECOND UPPER LEVEL LOW THAT DEEPENS ACROSS WESTERN WASHINGTON.
MODELS ARE IN GOOD AGREEMENT WITH A SURFACE LOW SPINNING UP OVER
NORTHWEST WASHINGTON SUNDAY AFTERNOON AND CONTINUING TO DEEPEN
AS IT TRACKS DOWN THE WESTERN COASTLINE. THIS WILL DO TWO
THINGS: (1) TIGHTEN THE NORTHERLY PRESSURE GRADIENT WITH COLD
CANADIAN AIR ADVANCING INTO THE REGION, AND (2) DRAW MOISTURE
NORTHWARD ACROSS THE REGION THAT OVERRUNS THE ADVANCING COLD
AIR. SNOW LEVELS WILL START OUT FAIRLY LOW AT AROUND 35000 FEET
ACROSS THE NORTHERN ZONES SUNDAY AFTERNOON DROPPING TO VALLEY
BOTTOM BY MONDAY MORNING. SNOW IS EXPECTED TO ACCUMULATE IN
THE NORTHERN MOUNTAINS THROUGH THE DAY SUNDAY. WARM ROAD
TEMPERATURES MAY MAKE IT DIFFICULT FOR SNOW TO ACCUMULATE
INITIALLY, BUT THESE TEMPERATURES ARE EXPECTED TO DROP
OVERNIGHT SUNDAY. STRONG DYNAMICS AND VERTICAL LIFT IN THE SNOW
GROWTH ZONE MAY ALSO PUSH SNOW LEVELS DOWN MORE SO THAN MODELS
ARE LETTING ON. SNOW WILL BE HEAVY AT TIMES AND I WOULDN'T BE
SURPRISED IF WE SEE PERIODS OF AN INCH OF SNOW PER HOUR
PARTICULARLY IN THE EAST SLOPES OF THE CASCADES WHERE EASTERLY
FLOW PRODUCES FAVORABLE OROGRAPHICS. A BIG CONCERN WILL BE FOR
ANY BACKCOUNTRY RECRATIONALISTS LOOKING TO CAMP IN THE
MOUNTAINS OVER THE WEEKEND. WEATHER CONDITIONS WILL DETERIORATE
RAPIDLY PARTICULARLY LATE ON SUNDAY. EXPECT WINTER CONDITIONS
AND COLD TEMPERATURES. MOUNTAIN PASSES WILL ALSO SEE THE
POTENTIAL FOR SNOW COVERED ROADS AND HEAVY AT TIMES FOR
WASHINGTON PASS AND SHERMAN PASS; HOWEVER, LOUP LOUP PASS,
STEVENS PASS, AND BLEWETT PASS WILL ALSO SEE THE POTENTIAL FOR
SNOW TRAVEL. BELOW ARE THE PROBABILITIES FOR SNOWFALL THRESHOLDS
OF AT LEAST 2", 4", AND 8" AND OUR MOUNTAIN PASSES:
MOUNTAIN PASS CHANCE OF 2+" CHANCE OF 4+" CHANCE OF 8+"
WASHINGTON 95% 85% 70%
SHERMAN 95% 75% 25%
LOOKOUT 35% 15% 0%
STEVENS 60% 35% 15%
BLEWETT 25% 10% 0%
LOUP LOUP 70% 50%20%
A WINTER STORM WATCH IS IN EFFECT FOR SUNDAY THROUGH MONDAY
MORNING ABOVE 3000 FEET ACROSS THE NORTHERN ZONES. HEAVIEST SNOW
AND BEST POTENTIAL FOR IMPACTS IS EXPECTED SUNDAY AFTERNOON
INTO SUNDAY NIGHT. /SVH
MONDAY NIGHT THROUGH THURSDAY: A QUIETER PATTERN RETURNS AS THE LOW
DROPS SOUTH OVER CALIFORNIA AND AN UPPER RIDGE BUILDS OFF THE COAST
PROVIDES A DRY NORTH TO NORTHWEST FLOW OVER THE INLAND NW. IT WILL
FEEL LIKE FALL AS LOW TEMPERATURES DROP INTO THE 20S AND 30S FOR
MOST OF THE REGION, AND DAYTIME HIGHS IN THE MID 50S TO LOW 60S.
JW
AVIATION
18Z TAFS: A DEEP UPPER LEVEL LOW PRESSURE SYSTEM SPINNING OFF
THE OREGON COAST WILL SLOWLY EJECT ACROSS THE INLAND NORTHWEST
TONIGHT. MOISTURE WILL INCREASE AHEAD OF THE LOW LATE THIS
AFTERNOON INTO THIS EVENING WITH MID LEVEL CLOUDS AND SHOWER
CHANCES INCREASING. WEAK INSTABILITY IN THE IDAHO PANHANDLE INTO
EXTREME EASTERN WASHINGTON MAY ALSO RESULT IN BRIEF THUNDERSTORM
DEVELOPMENT. SHOWERS WILL INCREASE PRIMARILY OVER THE CASCADE
CREST AND OVER EXTREME EASTERN WASHINGTON INTO THE IDAHO
PANHANDLE OVERNIGHT. WESTERLY WINDS INCREASE TONIGHT AND
CONTINUE INTO SATURDAY WITH GUSTS OF 15-25 KTS POSSIBLE THROUGH
SATURDAY MORNING. WINDS INCREASE FURTHER INTO SATURDAY
AFTERNOON. INCREASED BOUNDARY LAYER MOISTURE WILL RESULT IN
LOWERING CEILINGS FOR KGEG-KSFF-KCOE-KPUW-KLWS. MVFR CONDITIONS
WITH LOW STRATUS COVER WILL BE POSSIBLE ACROSS NORTHEAST
WASHINGTON INTO THE IDAHO PANHANDLE FOR SATURDAY MORNING.
FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: HIGH CONFIDENCE
IN VFR CONDITIONS TODAY. POTENTIAL FOR MVFR CONDITIONS FOR KPUW-
KGEG-KSFF-KCOE INCREASES AFTER MIDNIGHT UP TO 20% CHANCE THROUGH
12Z INCREASING TO A 50% CHANCE THEREAFTER THROUGH THE MORNING
SUNDAY. THERE IS A 10-20% CHANCE FOR THUNDERSTORMS LATE THIS
AFTERNOON AFTER 23Z IN THE SOUTHERN TO CENTRAL IDAHO PANHANDLE;
UNLIKELY THAT LIGHTNING WILL OCCUR WITHIN THE VICINITY KLWS-
KPUW-KCOE AT A LESS THAN A 10% CHANCE TODAY. /SVH
-----------------------
CONFIDENCE DESCRIPTORS:
LOW - LESS THAN A 30 PERCENT CHANCE
MODERATE - 30 TO 70 PERCENT CHANCE
HIGH - GREATER THAN A 70 PERCENT CHANCE
FOR ADDITIONAL PROBABILISTIC INFORMATION FOR NWS SPOKANE
AIRPORTS, PLEASE REFER TO THE AVIATION DASHBOARD ON OUR WEBPAGE:
HTTPS:/WEATHER.GOV/OTX/AVNDASHBOARD
PRELIMINARY POINT TEMPS/POPS
SPOKANE 43 57 40 50 36 52 / 60 40 70 80 80 20
COEUR D'ALENE 45 56 41 49 36 52 / 80 60 90 90 90 20
PULLMAN 41 55 38 47 38 54 / 60 60 90 80 80 30
LEWISTON 50 62 46 55 43 60 / 60 60 80 80 70 20
COLVILLE 34 57 29 50 29 51 / 60 70 70 80 90 30
SANDPOINT 40 52 36 47 31 48 / 80 70 100 90 90 30
KELLOGG 45 52 41 47 34 49 / 80 70 100 100 90 40
MOSES LAKE 42 62 39 54 40 54 / 20 30 20 60 70 50
WENATCHEE 46 61 45 52 38 51 / 30 30 40 60 80 50
OMAK 44 62 40 52 37 56 / 30 40 40 70 80 30
OTX WATCHES/WARNINGS/ADVISORIES
WA...WINTER STORM WATCH FROM SUNDAY MORNING THROUGH MONDAY MORNING
FOR NORTHEAST MOUNTAINS-OKANOGAN HIGHLANDS-WESTERN
OKANOGAN COUNTY.
AIR QUALITY ALERT UNTIL NOON PDT MONDAY FOR CENTRAL CHELAN
COUNTY-OKANOGAN VALLEY-WATERVILLE PLATEAU-WENATCHEE AREA-
WESTERN CHELAN COUNTY.
ID...WINTER STORM WATCH FROM SUNDAY MORNING THROUGH MONDAY MORNING
FOR NORTHERN PANHANDLE.
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